Reverse motion stop for duplicators



June 8, 1937. F. w. STORCK REVERSE MOTION STOP FOR DUPLICATORS Filed May12, 1956 Patented June 8, 1937 UNITED STATES REVERSE MOTION STOP FORDUPLICATO-RS Frederick W. Storck, Arlington, Mass, assignor to StandardMailing Machines Company, Everett, Mass, a corporation of MassachusettsApplication May 12, 1936, Serial No. 79,296

Y 4 Claims.

This invention relates to duplicators of the type having a printingcylinder or platen with a clamping device forsecuring a master copy tothe platen and the printing platen is stopped at an initial point aftereach cycle of operatiomand the invention more particularly relates to anautomatic reverse motion stop which is effective to stop the platen-at adeterminate posi 'tion other than its initial point and effective onlywhen the platen is rotated .contra to its normal direction of operativerotation. 7 r

' Duplicators of the herein referred to character are provided witharotary printing cylinder or platen which is provided with a clampingdevice adapted to secure a master copy to the platen. The platen isintermittently rotated and its stopping point between cycles sopositioned that clear sheets to be duplicated upo-n may be fedtoregisterin engagement with ,the master copyupon subsequent rotationofthe platen. A duplicating machine of this character is shown in myRe-issuelatent: No. 19,951.

Accomplishment of thisr desired function of feeding the'clear sheets forregistering engagement with the master copy requires an arrangeter willbe close to the path of the advancing end of the clear sheet so as toregister therewith with a minimum top margin when the master copy andclear sheet are engaged together in the'bight fo med by the platen andits coacting pressure roller. which engages the clear sheet underpressure with the master copy. The usual required arrangement of themachine elements to obtain the above function in a desired and efficientsequence does not readily lend itself toconvenience as the plateniclamp,when stopped in its normal dwell position for the beginning of a cycle,is either in an inaccessible position orii n a position not readilyexposed for the purpose of properly attaching the: master copy orremoving the same from the clamp without interference. j

When the master copy is to beattached or removed, in machines havingthese aforementioned elements so arranged, the operator rotates the drumuntil the clamp is in an exposed or desired position with the mastercopy free from contact with the pressure roller. I Y

In performing this positioning operation; the platen is usually rotatedcontra to its normal direction of operative rotation and its stoppingpoint controlled by the operator, therefore; care operator to stop theclamping device in the desired o-r exposed position. This positioningoperation is further inconvenienced when theduplicator is operated bymotor or like power and at a relatively high speed Under thesecircumstances, unless theoperato-r isalert, the platen will continuerotating until it is again engaged in its dwell period.

It is obvious that speed, convenience and simplicity in ope-ration areof 1 vital importance in duplicating machines of the herein referred tocharacter. I

Therefore, a primary object of my inventionis to provide a simple andeflicient positioning stop for a duplicator printing platen whichwill-be effective toarrest rotary movement of the platen in onedirection'only and at apoint other than its operating cycle dwellperiod, and whereby the clamping device may be positioned forconveniently attaching or detaching the master copy.

Another object 'of-"my present invention is to provide a stop device ofa rugged construction with a minimum number of working parts.

.With the above and other objects in view, my invention comprises anovel construction and arrangement of parts hereinaftendescribed andmore. specifically pointed out in theappended claims. I 11 r In the.accompanying drawing I have illustrated a preferred form of my automaticstop device, embodied with aportion' of a rotary duplicator; sufficienttoenable those skilled in the art to understand the construction andoperation thereof. 7 I

Referring to the drawing: 7 Fig. 1 may be termed a right hand endelevation of'a portion of'a rotary duplicator with my stop'devi'ceembodied'therewith. In this view one 'end frame is omitted'and themaster copy clamp is shown as it is positioned duringthe automatic dwellperiod of the duplicator. 1

Fig. 2 may be termed a left hand end elevation of the partssubstantially as shown at Fig. 1, and in this view the. mastercopy clampis shown arrested inits opposed position. Also, in this view the master.copy clamp is indicated by broken lines in its positioncorresponding'to that shownatFig.1.

Fig. 3 is a view of a portion of the elements illustrated at Fig. 2, butshows my stop. device in a different position, and

'Fig. 4 is substantially a plan view of the parts as shown at Fig. 2;

The duplicating machine rotation in suitable bearings in the sideframes.

The printing platen II is provided with a suitable clamping device I3for holding the endof the master copy. .M A pressure roller I4 engagesthe peripheral face of the platen I I and is mounted upon a'sha'ft I5which is journalled at its ends in suitable bearings in the side frames:-t

The duplicator drive In this instance, the mechanism for-intermittentlyrotating the printing platen includes an intermittent gear I6 which-iscontinuously..ro-

tated in any suitable manner. This intermittent gear I6-meshes with acoacting intermittent gear H which is securedto the drum of: the platenII. The intermittent gears I6, I! are ofthe usual construction wherein apredetermined portion of the periphery ofeach is free from teeth andcontinued rotation of the-gear I6 will not rotate the gear 'I'I untilthe blank space in the gear I6 has passed the blank space in thecoacting gear I1 and the teeth in both enmesh.-

Fora duplicatingcycle theintermittent driv- D ing gears I6, I'I rotatethe platen II in the ditioned automatic dwell period in the cycle ofoperation, and thus, during the dwell period, the end of the mastercopym, which isclamped at I3a,v by the clamp I3; is determinately positionedrelative to the bight I Ia formed between the platen- I I and its coacting pressureroller- I4, see Fig. 1. z.

As the clear sheets to be duplicated. upon are advanced inthedirectionof arrow -s, Fig.1, by feeding mechanism (not shown).,;the platen II isrotated so that the master m and clear. sheet meet in registeringengagement in the bightalla. of the pressure roller I 4 and platen I I.This side, to which the clear sheets are fed for engagement with themaster copy, may be conveniently termedthe feeding side of the platenII.

A duplicating machinehaving theabovecharacteristics is fully shown anddescribed in my aforesaid patent, therefore, further detaileddescriptionof the complete machine and the operation thereof is thoughtunnecessary. Further, it is to be understood that my invention;.is,notto be limited to a duplicating machine of the above specificconstruction and arrangement of parts which have been shown forthepurppse of illustrating an embodiment of my reverse motion stop.

The reverse motion stop 75 a slight rotary movement to be imparted tothe rection of arrow at and effect a determinate posi-' roller and thusreduces possible wear which might be occasioned by the continuedintermittent engagement of the arms with the roller.

The longer arm 20a, of the lever 20, projects into the path of a stopstud 24 which is secured to the platen II, in a positioned relation tothe master clamp I3, and rotated therewith. In this instance, the stud24 has a resilient roller freely mounted thereon which is adapted to en-;gage with the lever arm 20a.

Operation of the reverse motion stop As aforesaid, the platen II, in itsoperating cycle, is stopped with the clamped end of the master properlypositioned for registering engagement with an advancing clear sheetwhich is to be duplicated upon and, in this instance, as

' illustrated at'Fig. 1. During this operating cycle of duplicating, theplaten is rotated in the direction of arrow (1 and, as the stop roller25 engages with the arm 20 this arm is lifted upwardly out of itsengaging path. Upward movement of the arm 20a is limited by engagementof the arm 201) with the roller 22', see Fig. 3. As the platen I Icontinues its rotary movement, the roller 25 releases'the arm 20a-whichis then permitted, in this instance through its own weight, to return toits normalposition in engagement with the roller 25 with the arm 20aagain extending into the path of the stop roller 25.

When it is desired to removeor secure a master copy to the platen, theplaten is conversely rotated, in the direction of arrow 12, until thestoproller 25 is engaged withthe arm 20a,'see Fig. 2, and arrestsfurther rotative movement of the-platen I I and thus positions the clampI3 where the master copy may be conveniently attached or detached.

- It is obvious that thisjreverse motion stop must be positionedandeffective during the interim of the continuedrotation' of the platen II,therefore, inthe hand operated type of duplicator, 'uponengagement ofthereverse motionstop, the operator merely ceases operation ofthe'm'anual means. In the power driven type of duplicator,- as theplaten is locked during its reverse motion, it is obviousthat the powerbelt .or' connectionmust be arranged or permitted'to slip until'thepower is disengaged by the operator. I

Excessive shock to the working parts during the stopping of the reversemotion is prevented to a degree by means of the resilient stop rollers22 and 25 with which the lever locks during this stopping function;f'Having thus described my invention, what I claim is:

1. 'A rotary duplicator having a printing platen with means for securinga master copy thereto andmeans for rotating said platen in conversedirectionswithf a determinate positioned dwell period in its cycle ofrotation, a substantially U'-sha'ped lever pivotally secured relative tothe end of said platen, the opposed-arms of said lever being of unequallength, a limiting member disposed between said arms to limit thepivotal movement of said lever, a projection associated with said platenand'rotated therewith in an engaging path relative to one arm of saidlever that is normally disposed in the path of said projection and in amanner whereby said arm is;.displaced, when said platen is rotated inits normal operative direction, and said arm is operatively engagedbetween said limiting. members and said projection when said platen isconversely rotated, and whereby rotative movement of said platen isarrested in a. second determinate position.

2. A rotary duplicator having a printing platen with means for securinga master copy thereto and means for intermittently rotating said platenin opposite directions with a determinate positioned dwell period in itscycle of rotation, in combination with a member having a limited pivotalmovement and cooperating with a stop member which is associated withsaid platen, said first member continuously engaging in the path of saidstop member and said members being adapted to operatively engage toarrest rotative movement of said platen when said platen is rotatedopposite to its normal operative direction and at a point other thansaid dwell period.

3. A rotary duplicator having a printing platen with means for securinga master copy thereto and means for conversely rotating said platen witha determinate positioned dwell period in its cycle of rotation, a stopassociated with said platen and. a coacting' member for said stop whichis continuously disposed in the path of said member and adapted toarrest rotative movement of the printing platen at a point other thanthe position of said dwell period when said platen is rotated oppositeto its normal operative direction, said stop and member being disposedto permit a free continued rotation of said platen in its normaloperative direction.

4. A rotary duplicator having a rotative printing platen with means forsecuring a master gage in the pathof an element of said platen to arrestmovement thereof and independent of said dwell period, only whensaid'platen is rotated opposite'to its normal operative direction.

FREDERICK W. STORCK.

